CVE-2026-43085

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_log: initialize nfgenmsg in NLMSG_DONE terminator When batching multiple NFLOG messages (inst->qlen > 1), __nfulnl_send() appends an NLMSG_DONE terminator with sizeof(struct nfgenmsg) payload via nlmsg_put(), but never initializes the nfgenmsg bytes. The nlmsg_put() helper only zeroes alignment padding after the payload, not the payload itself, so four bytes of stale kernel heap data are leaked to userspace in the NLMSG_DONE message body. Use nfnl_msg_put() to build the NLMSG_DONE terminator, which initializes the nfgenmsg payload via nfnl_fill_hdr(), consistent with how __build_packet_message() already constructs NFULNL_MSG_PACKET headers.

References

• https://git.kernel.org/stable/c/15d209bccf9273b4a8b4e579ba0e92d065b6ec8c
• https://git.kernel.org/stable/c/1f3083aec8836213da441270cdb1ab612dd82cf4
• https://git.kernel.org/stable/c/368c22aea490f6f50df831b4f9e3623787686c5b
• https://git.kernel.org/stable/c/d1399632ba255d2e02c757af5d9f5d9279ce168c
• https://git.kernel.org/stable/c/d552bcfca323d175664d7444989b04f55666978a